///   * Must set `status` to `TF_FAILED_PRECONDITION` if `path` points to a
  ///     directory or if it is invalid (e.g., malformed, or has a parent entry
  ///     which is a file).
  ///   * Might use any other error value for `status` to signal other errors.
  ///
  /// REQUIREMENTS: If plugins implement this, they must also provide a filled
  /// `TF_RandomAccessFileOps` table. See "REQUIRED OPERATIONS" above.